Validation of age-adjusted pelvic incidence minus lumbar lordosis and lordosis distribution index for assessing adjacent-segment disease after short-level lumbar fusion surgery: minimum 5 years of follow-up

Age-adjusted PI-LL may have limited ability to predict the development of ASD. LDI could exert an important effect on diagnosing the occurrence of ASD in the cases with low and average PI, but segmental lordosis was a more significant risk factor than LDI in individuals with high PI.